Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC B1547 0B: Seat Back Rotation Motor CircuitDTC B1770 0B: Seat Motor (Assembly Horizontally) Circuit
DTC B1785 0B: Seat Motor (Recline) Circuit
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Folding Seat Horizontal Position Sensor Signal | B2375 0A | B2375 0A | B2375 0A | -- |
Folding Seat Recline Position Sensor Signal | B1825 0A | B1825 0A | B1825 0A | -- |
Folding Seat Rotation Position Sensor Signal | B1548 0A | B1548 0A | B1548 0A | -- |
Folding Seat Horizontal Motor Forward Control | B1770 0B | B2375 0A or 1 | -- | -- |
Folding Seat Horizontal Motor Rearward Control | B1770 0B | B2375 0A or 1 | -- | -- |
Folding Seat Recline Motor Forward Control | B1785 0B | B1825 0A or 1 | -- | -- |
Folding Seat Recline Motor Rearward Control | B1785 0B | B1825 0A or 1 | -- | -- |
Folding Seat Rotation Motor Forward Control | B1547 0B | B1548 0A or 1 | -- | -- |
Folding Seat Rotation Motor Rearward Control | B1547 0B | B1548 0A or 1 | -- | -- |
Low Reference | -- | B1548 0A, B1825 0A, B2375 0A | -- | -- |
1. Power Third Row Seat Inoperative | ||||
Circuit/System Description
Battery positive voltage is supplied to the rear seat module (RSM) from the 30 A RSM fuse located in the left rear fuse block. When commanded, this voltage is used by the RSM to power the seat motors through there respective motor control circuits. During seat operation, the driven motor current is monitored through the motor control circuits by the RSM. When an overcurrent condition is detected, the RSM disables the seat motors in order to protect the internal RSM circuitry.
Conditions for Running the DTC
The RSM monitors for overcurrent only when the seat motors are active.
Conditions for Setting the DTC
The RSM will set this DTC when the current draw on an active motor exceeds a calibrated threshold.
Action Taken When the DTC Sets
| • | If the seat is moving when this condition occurs, the operation will be aborted. |
| • | The RSM will not respond to all third row seat switch inputs. |
| • | The RSM will set a history DTC. |
Conditions for Clearing the DTC
| • | The RSM does not detect an overcurrent condition during seat movement. |
| • | The history code will clear if the RSM does not detect an overcurrent for 100 ignition cycles. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Power Seats System Description and Operation
Electrical Information Reference
Scan Tool Reference
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the appropriate seat adjuster motor for which the DTC set.
- Connect a test lamp between control circuits terminal 1 and terminal 2.
- Ignition ON, command the appropriate motor to the Forward and Rearward directions with a scan tool. The test lamp should momentarily turn ON when commanding the Forward and Rearward states.
- If all circuits test normal, test or replace the seat motor.
| ⇒ | If the test lamp remains OFF during either of the commands, test the control circuits for a short ground. If the circuits test normal, replace the RSM. |
Repair Instructions
Important: After performing this diagnostic test and electrical or component repairs have been completed, the folding seat will be in an unknown state and out of calibration with the RSM. The RSM must be calibrated before the folding seat system will operate. Refer to Power Folding Seat Calibration .
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for RSM replacement, setup, and programming |
